The invention relates to a cup made of a paper material or a material which can be processed in a similar manner to paper and has a fillable interior which is formed by means of a casing which is conical at least in certain sections and a base. The base is connected in an essentially fluid-tight manner to the casing in the region of the lower end of the interior. The cup has an outer casing which surrounds the casing at least in certain sections, with the result that an insulating space is formed between the casing and the outer casing.
The insulating space serves here to keep a beverage contained in the interior warm for as long as possible. This is done, in particular, by preventing the transportation of heat between the beverage and the surrounding atmosphere.
It has become apparent that for specific applications the introduction of an insulating material into the insulating space can be advantageous. As a result, the insulating effect can be increased and a constant distance can be maintained between the outer casing and the casing. This can be advantageous, in particular, when gripping or compressing the cup while drinking. If the outer casing and the casing touch, the insulating effect is reduced to an undesired extent.
Suitable insulating materials are, for example, insulation materials insofar as they can be positioned between the outer casing and the casing by a process of whatever kind. However, it has become apparent that typical insulating materials have a certain degree of porosity or brittleness. It is therefore possible for the insulating material to “crumble”, which does not necessarily worsen the insulating effect but can lead to a situation in which parts of the insulating material fall into another cup when cups are stacked together. This insulating material can float after a beverage has been placed in the cup and can irritate the customer of the hot beverage. In this case, the customer may assume that the beverage is contaminated and refuse to consume it.
The problems mentioned above lead to a situation in which, in the case of cups of the generic type, the use of insulating materials is frequently prohibited, in particular in the case of cups which are to be stacked one in the other.
The invention also relates to a method for manufacturing a cup in which the problem arises that the manufactured cup of the generic type is prone to the same disadvantages which have just been described above.
The invention is intended to specify a cup made of a paper material or a material which can be processed in a similar manner to paper, in which cup an insulating material is provided and which can nevertheless be stacked and handled without problems. Furthermore, an object of the invention is to provide a method for manufacturing such a cup.
The invention relates to a cup made of a paper material or a material which can be processed in a similar manner to paper and has a fillable interior which is formed by means of a casing which is conical at least in certain sections and a base. The base is connected in an essentially fluid-tight manner to the casing in the region of the lower end of the interior. The cup has an outer casing which surrounds the casing at least in certain sections, with the result that an insulating space is formed between the casing and the outer casing.
According to the invention there is provision that                the insulating space is at least partially filled with insulating material, and        a lower seal, which runs completely around the circumference, is formed at least underneath the insulating material to prevent the insulating material from escaping between the casing and the outer casing.        
By means of the seal provided according to the invention it is effectively possible to prevent the insulating material from escaping on an underside of the cup. In typical stacked arrangements of such cups, this underside is normally located particularly low in another cup, with the result that in cups of the known type there is a particularly large risk that insulating material will enter another cup at this point. The cup according to the invention therefore permits the advantages which arise from the provision of an insulating material in the insulating space to be combined without problems with the advantages which arise from stacking the cups.
The paper material or the material which can be processed in a similar manner to paper is, in particular, a material which is resistant to the effect of typical beverages over typical periods of time in which the beverage is stored in the cup. For this purpose, plastic elements can also be integrated into the paper material. Likewise, it is possible to use a plastic material which can be processed in a similar manner to paper, wherein a conical sleeve and a pot-shaped base are therefore manufactured from planar material and then connected to form a finished cup.
The lower seal is preferably formed underneath the entire insulating material which is arranged between the casing and the outer casing. As a result, the sealing effect of the seal extends to the entire insulating material which is present in the cup. This can effectively prevent parts of an insulating material which is possibly arranged underneath the seal from dropping out.
According to one embodiment there is provision that                the lower seal is formed by the outer casing being bonded, adhered or sealed to the casing at a lower shoulder,        wherein the lower shoulder is formed on the outer casing and extends towards the casing.        
As a result, an additional reinforcing effect of the shoulder can be obtained and the outer casing can easily be connected to the casing at a suitable point.
According to one alternative embodiment, the lower seal is formed by rolling the outer casing towards the casing and bonding, adhering or sealing it to the casing. The rolling process serves here, in particular, to maintain a distance between the outer casing and the casing.
According to one embodiment, the outer casing is spaced apart at its lower edge from the casing, and the lower seal is embodied in such a way that it is spaced apart from the edge further in the upward direction. In such an embodiment, it is possible to dispense with bending or rolling the outer casing.
In particular in this case the lower seal is preferably embodied in the form of a circumferential adhesive bead, pulp bead or sealing bead or in the form of a sealing lip. In this context, a circumferential bead can advantageously form a materially joined connection between the outer casing and the casing. A sealing lip is typically an element which protrudes from the casing towards the outer casing or else from the outer casing towards the casing. The sealing lip encloses here, in particular, the space between the outer casing and the casing in such a way that no parts of the insulating material can drop out in the downward direction. In this case, a bonded connection is typically provided spaced apart from the sealing lip, which bonded connection ensures that the outer casing is arranged sufficiently close to the casing that the outer casing presses with a certain stress against the sealing lip or that the sealing lip presses with a certain stress against the casing. Therefore, the sealing effect which is necessary here can be achieved even without a materially joined connection or adhesive bond having to be formed between the outer casing and the inner casing at the seal.
According to one preferred embodiment there is provision that above the insulating material, a circumferential upper seal is formed completely around the circumference in order to prevent the insulating material from escaping between the casing and the outer casing. Therefore, insulating material can be prevented from escaping even at an upper side of the cup. This is relevant, in particular, when the cup is stored upside down, for example, during transportation or else for the purpose of storage in a system catering restaurant, i.e. the interior is open in the downward direction in this state. This permits, for example, the penetration of dust or of undesired objects into the interior to be prevented.
The upper seal is preferably formed above the entire insulating material which is arranged between the casing and the outer casing. Therefore, the sealing effect of the seal extends over the entire insulating material which is present in the cup. This can effectively prevent parts of an insulating material which is possibly arranged above the seal from dropping out.
According to one embodiment there is provision that                the upper seal is formed by bonding, adhering or sealing the outer casing to the casing at an upper shoulder,        wherein the upper shoulder is formed on the outer casing and extends towards the casing.        
Therefore, an additional reinforcing effect of the shoulder can be achieved and the outer casing can be easily connected to the casing at a suitable point.
According to an alternative embodiment, the upper seal is formed in that the outer casing is rolled towards the casing and is bonded, adhered or sealed to the casing. The rolling serves here, in particular, to maintain a distance between the outer casing and the casing.
According to one embodiment, the outer casing is spaced apart at its upper edge from the casing, and the upper seal is embodied in such a way that it is spaced apart from the edge further in the downward direction. With such an embodiment, it is possible to dispense with bending or rolling of the outer casing.
In particular, in this case, the upper seal is preferably embodied in the form of a circumferential adhesive bead, pulp bead or sealing bead or in the form of a sealing lip. In this context, a circumferential bead can advantageously produce a materially joined connection between the outer casing and the casing. Reference should be made to the statements further above with respect to the use of a sealing lip.
A number of completely circumferential, central seals are preferably arranged between the casing and the outer casing, wherein insulating material is arranged both underneath and above each central seal. Therefore, a seal which acts only for a part of the insulating material contained can be also provided along a vertical direction of the cup. This can be advantageous, for example, if so much insulating material is arranged above such a central seal that a single lower or upper seal would no longer be sufficient effectively to prevent said material from escaping. By means of the central seal, the quantity of insulating material which can be contained in the insulating space can therefore also be increased.
According to one embodiment, the insulating material is formed in one or more large-area layers. In an embodiment which is an alternative to this, or even can be combined therewith, the insulating material is formed in one or more circumferential beads. Large-area layers typically extend over a considerable part of the cup in the vertical direction here. On the other hand, circumferential beads typically have a vertical extent which is considerably smaller than the entire vertical extent of the cup.
According to one embodiment, a number of central bonding points are arranged between the casing and the outer casing, wherein the central bonding points are arranged over the lower seal and under an upper edge of the outer casing and/or under the upper seal. Such bonding points can be suitable, in particular, for bonding the outer casing to the casing when sealing lips are used, wherein such a bonded connection can, for example, be made in a vertically central fashion. This is advantageous, in particular, insofar as the sealing lips themselves do not provide a materially joined connection or adhesive bond and therefore also no holding effect. Furthermore, in order to bring about the sealing effect of sealing lips a certain degree of prestress has to be achieved, as has been described further above. Such prestress can also be achieved with the bonding points just mentioned.
In contrast to the central seals mentioned further above, a bonding point does not necessarily have to be embodied running completely around, since it does not have the function of preventing insulating material from escaping but merely has the function of holding the outer casing against the casing.
According to respective embodiments, one, a plurality of or all of the seals can be embodied by means of a hot-melt adhesive, which can also be referred to as a hot melt. Likewise, one, a plurality of or all of the seals can be embodied by means of pulp. Such embodiments have proven advantageous.
The insulating material is advantageously formed from a physiologically harmless material. In particular, maize starch can be used for this. Therefore, it is possible to ensure that even in the event of a seal failing and the insulating material undesirably entering a beverage, there is no risk of damage to health.
In order to stack cups, a correspondingly long skirt, which can rest on a cup lying underneath it, can preferably be provided, or else a stacking shoulder which is formed on the inside in the cup can be provided. This facilitates the stacking of cups, since in this way a defined distance is maintained between stacked cups. Excessive tilting of the cups, which under certain circumstances leads to permanent deformations of the cups or to difficulties when removing cups from a stack, can therefore be effectively avoided. The stacking shoulder is preferably running all around but can also be formed only in certain sections.
The invention also relates to a method for manufacturing a cup according to the invention made of paper material or a material which can be processed in a similar manner to paper, wherein the method comprises the following steps:                essentially fluid-tight connection of a conical casing and of a base,        application of an insulating material to the casing,        attachment of an outer casing to the casing, and        formation of at least one seal to prevent the insulating material from escaping between the outer casing and the casing.        
By means of the method according to the invention it is possible to manufacture a cup which has the advantages already mentioned further above. With respect to the cup it is possible here to have recourse to all the variants and embodiments described further above. Explained advantages apply correspondingly.
It will be understood that the aforementioned steps can be carried out in the specified sequence, but also in another sequence. For example, the insulating material can firstly be applied to the casing and subsequently the outer casing can be attached to the casing. Alternatively, for example the outer casing can firstly be attached to the casing and subsequently insulating material can be introduced into the insulating space formed as a result. Likewise, the seal can be implemented before or after the application of the insulating material. This applies both to the lower and also to a possible upper seal.